Low, next to NO pressure

My pump seems as though it's sucking tons of air, but the line from the pump to the skimmer is airtight. I used a bladder type pressure device to charge the line and waited for leaks. After about 30 sec. it shot the plug I had in the pump inlet out like a shotgun. Didn't see any leaks.
My pump motor basket is only about half full of water. Its sloshing it in there fast but can't keep up. I've stuck my fingers in all the holes and the impeller feels normal and clean. After I turn my pump on and back off there is so much pressure I can't even get the lid off the pump basket.
Lastly the filter is running at 0-4 lbs pressure. When I turn the valve to recirculate it does the exact same thing minus the filter pressure.

Is my pump trashed?

Welcome to the forum.
Are you sure it isn't something as simple as the gasket for the pump basket lid leaking air somewhere? For air it only takes a tiny, sometimes almost invisible leak to let enough air in to mess things up. This could also be the reason for low pressure. Clean the gasket thoroughly and coat it with a good silicone lube....Jacks or equivalent. Available at most pool stores.
Not sure what you meant by this statement.....'After I turn my pump on and back off there is so much pressure I can't even get the lid off the pump basket.'

Al

Hello and thanks for the reply.
I've cleaned off any debris and put silicon on the O ring. I'll stop off and get a new one today just to make sure.

What I was trying to say was that when I shut the pump down the vacuum on the basket lid is so tight I can't hardly get it off. It had to open up the bleed valve on the filter and use a rubber mallet to get the lid off the pump basket once today.

If your pump is above the waterline of the pool, it will take, in some cases, minutes to "prime" (i.e....pull all the air from the system). Are you giving it that time?

Forgive me for stating the obvious, but if you are new to pumps, than can sometimes surprise you.

Regardless of the reason for the air in the pump, you will not get good pressure 'til that air is withdrawn from the system...I'm pretty sure that is why your guage is indicating 0-4.

With that much vacuum on the lid with the pump shut off I'm guessing the pump is a few feet above the pool water level. Something doesn't compute. If that is the case I'm surprised it even primes. Seems like you definitely have an air leak somewhere.
Al

I had a similiar situation when the o-ring to my offline chlorinator failed....don't know if that helps or not :confused:

Looking through all these posts, I get the feeling you have a partial blockage from the skimmer to the pump. If you have a main drain, try opening it up to see if that makes any difference. If it improves substantially, then you definitely have some form of blockage. The high vacuum you mention seems to imply that. You say you have to open the filter bleed valve to release the vacuum.

Is there a valve in the skimmer line that is not fully open?

Is the pump overized for the duty?

Have you tried to get a water flow back to the skimmer frm the pump basket housing?

Trying to look at all the things you need to help you fix this.

Pat

It seems as though I've found a new home when it comes to pools. Thanks everybody. I am pretty new to pools, this will be my third season. The first season I made all the rookie mistakes and then some. Ended up with black alagae and every other hideous std in my pool.
Second season I drained, scrubbed and pressure washed and had a pretty good year last year. I never had equipment issues till this year so I am a ameatuer with pumps.

Today I ran a snake down my skimmer towards the pump. I only had a 20 ft. snake so I went as far as I could. When I ran water to waste the pump basket actually filled 90% with water. I turned to filter and I'm getting the same. Now running almost 10 pounds of pressure but still have the white water effect in the basket. I'm wondering if I partly dislodged something in the skimmer line.
Next step is to find a longer snake, unless you guys have any other ideas on how to clear it out?

update: The only way I can get the filter working is to get a good prime using waste. When I waste there are very few bubbles in the basket. I then quickly switch to filter and it works as above (I do turn off the pump first). If I just start off in filter I never get enough water flowing to have any pressure.

Im currently letting it recirculate. Waters flowing pretty good, but still have some bubbles coming out of jets.

I had this problem after opening last season, and battling an algae bloom. Couldn't figure out why pump wouldn't prime! Checked o-ring seals on both pump basket and chlorinator (which is now never used), etc. After many backwashes, my pool water level was a little low. Low enough to cause air to enter through skimmer. Once I added more water, actually put hose directly in skimmer, problem went away.

May your problem be that easy!

CaryB

I've put the hose in the skimmer. Relubed both O rings. My chlorinator won't fill with water unless I unscrew the lid a little with pump running. Then it fills to the top and i (assume) its circulates. Don't really know.
Also, the pump won't prime unless i put it in waste, and only without the blue hose on. If the pump has to fight any resistance at all it won't prime. Once it gets a good prime i can switch to filter and hold my 10 lbs of pressure. There is alot of very small bubbles coming out of the jets still though.

I really appreciate all the suggestions.

RE: air bubbles via return jets

My return jets did this and it was due to "channels" and an air pocket in my sand filter. A good minute on the RINSE feature to stir up and resettle the sand did the trick. No more bubbles! I did not, however, pay attention to pressure gauge during this episode. I'm pretty sure my pump primed and suction was good, though.

Hope this helps and keep us posted.

CaryB

You're going to see constant bubbles in the return line for one or two reasons. Suction side leak or cavitation.
Air leaks after the pump, will not cause bubbles (air being introduced into the lines) as this is pressure side. The ONLY exception is a venturi jet or spa hydrotherapy jet, that are designed to suck air in. Otherwise water will be pressurized out of the pipe.
Suction side leaks will appear as bubbles in the pump basket or the pump basket not being able to fill with water. Since you've managed to snake it and get it 90% filled, most likely Pat was correct in diagnosing a blockage in your suction line.
Blockage in the line will not be bubbles coming into the pump basket area, but rather, the pump basket not filling up. Can you send the snake from the skimmer side? Perhaps some straight muriatic acid into the skimmer side and let it sit an hour to let it dissolve whatever may be blocking the line?? Then flush it out with your garden hose into the skimmer port, before turning your pump back on. Watch the debris buildup in the pump basket though.

Cavitation would make your pump sound louder than normal.

Hi, everyone,

This is an interesting issue. I'm not at all confident about any blockage in the suction side however. The reason is when he switches to "waste" his pump primes but it does not prime from the "filter position". That, in my mind, eliminates the suction side since his issue only occurs in the "filter" position.

So, if that assumption is correct, the issue has to be on the pressure side. Does that make sense? If it does, what kind of restriction on the pressure side (and in the filter or filter plumbing only) could prevent the pump from priming.? I simply don't have an answer but the suction side blockage doesn't seem to work, either.

I'm particularly puzzled by the fact that, once primed, the system seems to run fairly normal (10psi, water flowing "pretty good"). If something in the system is keeping the pump from priming, wouldn't it make sense that the sytem wouldn't perform normally.

I know I've posed questions and answered nothing but it seems to me the vacuum side restriction is not correct. I sure hope there is a clear outcome on this....I'd love to know what it is.

I stuck my shop vac into the skimmer to blow it out to the filter. I had a DE clog in there because of adding too much without making the "DE slurry". If you have a clog in the line between the skimmer and the pump, maybe a shop vac will help you too.

Also - I figured this out b/c I turned off the skimmer input line and only used the bottom drain line. Guess what - it didn't have the flow issue. So, it was something in between the skimmer and pump. I was just glad it was a clog and not a water leak!

Well, I'm going out of town on business for a few days. This post will probably get lost, but I will re-erect as soon as I get home and am able to try the shop vac and some muratic acid. Thanks again

Any chance there is a malfunctioning check valve that could be making the problem worse? Sounds like a suction side air leak somewhere to me since you keep seeing bubbles even after getting is primed.

I just had a low pressure problem after a day of vacuuming. The symptoms were the same as stated here. Eventually after messing around with the rinse a few times, and then waste, the partial blockage blew out of the way and water just started gushing out of the waste line. What I'm saying is, what appears not to be a blockage just may be.

At the top of the filter there should be a bleed valve. Are you leaving this open to expel all the air in filter when first running the pump?

i'm finally going to be home tonight. I think there is a partial blockage also. I was thinking about dropping in a wiffle golf ball and seeing if it comes out the other side. if not i guess I'll go rent a snake.

I beleive I found the problem. The pool pump basket is cracked. I finally got pressure up to 20 lbs. and when I turned it off I saw water squirt out of the bottom-front of the pump.
Now, do I use the same motor and try to find replacement parts, or go with a new pump?
I currently have a hydramax II, 1.5 hp. I have no idea how old it is.
Thanks for stickin with this one.